Carburetion system



Oct. 16, 1956 v T MAVlTY CARBURETON SYSTEM Filed Sept. 28, 1953 w Smilmv W WR. d w 0 a m N .MQ vm www um mm 1 mv 4 m wm m .Jm/ Hf wm mm w ww V NN vm. mbm ww mm mm BY WWWM 1 United States Patent CARBURETION SYSTEM Victor T. Mavity, Dothan, Ala. Application September 28, 195B, Serial No. 382,540

9 Claims. (Cl. 48-184) This invention relates in general to improvements in carburetion systems, and more specifically to a carburetion system for use with gaseous fuels.

The primary object of this invention is to provide an improved carburetion system for use with gaseous fuels which may be controlled by a simple linkage in the same manner as conventional carburetors and which is responsive to the demands of an engine with which the carburetion system is associated for supplying gaseous fuel thereto in combination with air to form a fuel-air mixture of correct proportions.

Another object of this invention is to provide an improved carburetion system for supplying gaseous fuel to an internal combustion engine, the carburetion system including a fuel supply shut-off valve which is actuated in response to a vacuum produced by rotation of the engine, the fuel shut-off valve forming a safety valve for the fuel supply system.

Another object of this invention is to provide an improved carburetion system for use with gaseous fuels which is extremely simple in construction and which may be quickly and easily attached to conventional internal combustion engines.

A further object of this invention is to provide an improved carburetion system for gaseous fuels which includes both a fuel shut-off valve and a fuel supply regulating valve, the fuel supply regulating valve being actuated by a differential in pressure within an associated air intake line on opposite sides of a restriction therein.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a side elevational view of the carburetion system which is the subject of this invention and shows the same attached to an intake manifold of an internal combustion engine, a portion of the air intake line being broken away; and

Figure 2 is an enlarged fragmentary sectional View showing the construction of the main elements of the carburetion system.

Referring now to the drawings in detail, it will be seen that there is illustrated an intake manifold of an internal combustion engine. Connected to the intake manifold 10 for supplying a fuel-air mixture thereto is an air intake line 12. The air intake line 12 is provided with an air intake fitting 14 at the end thereof opposite from the end connected to the intake manifold 10.

Carried by the air intake line 12 intermediate its ends and communicating therewith is a fuel supply line 16. The fuel supply line 16 has removably connected thereto a fuel supply regulating valve which is referred to in general by the reference numeral 18.

The fuel supply regulating valve 18 includes a housing 20 which has threadedly engaged therein one end of the fuelf-supplyline 16. Disposed'at `right angles to the fuel supply line 16 is an internally threaded bore 22 in the housing 20 in which is fitted a flow control tting 24. The flow control fitting 24 includes an orifice 26 which, together with the fuel control rod 34, offers at all engine speeds and loads the required net opening to permit the correct amount of gaseous fuel to enter the fuel supply line 16. The end of the housing 20 opposite from the internally threaded bore 22 is closed by a cap 28. The cap 28 is connected to the housing 20 by fasteners 30 which also connect to the housing 20 between the housing and the cap 28 a diaphragm 32. Carried by the diaphragm 32 is a fuel dow control rod 34 which has the free end thereof so shaped and positioned in relation to shape of orifice 26 that the flow of gaseous fuel into fuel supply line 16 will be always proportional to load of the engine.

It will be noted that the cap 28 is of the hollow type and includes a compartment 36. The compartment 36 is connected to the air intake line 12 by piping 38. Disposed in the air intake line 12 between the connection of the piping 38 therewith and the connection of the fuel supply line 16 therewith is a flow restrictor 40. The flow restrictor 40 is provided with au orifice 42 of a reduced size therethrough. Due to the positioning of the flow restrictor 40 in the air intake line 12, it will be seen that the pressure on the fuel supply line side of the diaphragm 32 will be greater than the pressure on the cap side of the diaphragm 32 inasmuch as there will be a greater vacuum on the engine side of the fiow restrictor 40.

In order to properly position the flow control rod 34 and to selectively varythe effect of the differential in pressure on opposite sides of the diaphragm 32, there is provided a spring 44. The spring 44 is disposed within the compartment 36 and urges the diaphragm 32 to the left to an orifice closing position. The tension of the spring 44 is varied through the use of an adjustable set screw 46 carried by the cap 28.

The carburetion system which is the subject of this invention also includes a fuel supply shut-off valve which is referred to in general by the reference numeral 48. The fuel supply shut-off valve 48 includes a housing 50 which has a fitting 52 at one end thereof. The interior of the housing S0 is communicated with the interior of the fuel supply regulating valve 18 through a connector 54 which extends between the fitting 52 and the fitting 24.

Extending through an opposite side of the housing 50 from the fitting 52 is a fuel supply line 56. The opposite end of the fuel supply line 56 may be connected to any convenient pressurized gaseous fuel source. The fuel supply line 56 terminates in an upwardly extending portion 5S.

The upper end of the housing 50 is closed by a cap 60. The cap 60 is removably secured to the housing 50 by suitable fasteners 62. The fasteners 62 also secure in place between the housing 50 and the cap 60 a flexible diaphragm 64. The diaphragm 64 overlies the portion 58 of the fuel supply line 56 and normally closes the same.

In order that the diaphragm 64 may be urged to a closed position, there is disposed within the connes of the cap 60 a spring 66. The spring 66 urges the diaphragm 64 downwardly and the pressure exerted by the spring 66 is varied by an adjusting screw 68 carried by the cap 60.

In order that the diaphragm 64 may be unseated olf the end portion S8 of the fuel supply line 56, there is communicated with the interior of the cap 60 the interior of the intake manifold 10 by piping 70. The piping 70 per` mits the producing of a vacuum within the cap 60 so as to urge the diaphragm 64 upwardly against the downward urging of the spring 66, whereby fuel may be supplied to the fuel supply regulating valve 18.

Disposed in the air intake line l2 adjacent the intake manifold 1Y0 is a butterfly valve 72. The butterfly valve 72 includes a pivotally mounted shaft '74 which may be connected to any conventionalv throttle control mechanism.

In the operation of the carburetion system, the internal combustion engine (not shown) of which the intake manifold is a part is turned over through the use of its starter or other starting mechanism. This causes the production of a vacuum within the intake manifold fd. A vacuum within the intake manifold it) results in the upward movement of the diaphragm 64 to permit fuel to flow into the fuel supply regulating vaive i8. inasmuch as the normal position of the tiow control rod 34 permits the passage of a small amount of fuel through the orifice 26, fuel passes down into the air intake line 12 through the fuel supply line 16 and mixes with the air to form a fuelair mixture which is supplied to the internal combustion engine through the intake manifold lfb. The engine then starts. The fuel being supplied to the intake manifold 10 through the normal setting of the fuel supply regulating valve 18 is sufficient to permit the internal combustion engine to idle.

When it is desired to run the internal combustion engine at a speed higher than the idling speed, the butterfly valve 72 is moved towards an open position in the same m-anner as the butterfly valve of a conventional carburetor. This permits the drawing in of a greater amount of air through the orifice 42. Further, this creates a greater differential in pressure on opposite sides of the diaphragm 32 and causes the diaphragm 32 to move to the right against the urgence of the spring 44. This results in the flow control rod 34 moving further out of the orifice 26 and permitting a greater amount of fuel to pass through the fuel supply regulating valve 18. It will be understood that the fuel-air ratio will remain substantially constant at all times so as to obtain the maximum efficiency from the carburetion system.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

l. A gas carbureting system comprising an air intake line, a fuel intake line carried by and communicating with said air intake line, a fuel supply regulating valve in said fuel intake line, a fuel supply line connected to said fuel intake line, a fuel shut-off valve disposed between said fuel supply line and said fuel intake line, a selectively controlled valve in said air intake line for controlling the passage of a fuel-air mixture therethrough, said fuel supply regulatingvalve including a restricted orifice, a ow control rod selectively positioned in said orifice, a pressure actuated diaphragm connected to and positioning said flow control rod, a restriction in said air intake line on the engine side of said fuel intake line, said diaphragm having one side communicated with the air intake line on the upstream side of the restriction in said air intake line, the other side of the said diaphragm being communicated with the air intake line on the downstream side of said restriction in the air intake line, said diaphragm thus being positioned by the difference in pressures of the fuel-air mixture on opposite sides o-f said restriction.

2. A gas carbureting system comprising an air intake line, a fuel intake line carried by and communicating with said air intake line, a fuel supply regulating Valve lin said fuel intake line, a fuel supply line connected to said'fuel intake line, a fuel shut-off valve disposed between said fuel supply line and said fuel intake line, aselectively controlled valve in said air intake line for controlling the passage of a fuel-air mixture therethrough, said fuel supply regulating valve including a restricted orifice, a flow control rod selectively positioned in said orifice, a pressure actuated diaphragm connected to and positioning said ow control rod, a restriction in said air intake line on the engine side of said fuel intake line, said diaphragm having one side communicated with the air intake line on the upstream side of the restriction in said air intake line, the other side of said diaphragm being communicated with the air intake line on the downstream side of said restriction in the air intake line, said diaphragm thus being positioned by the difference in pressures of the fuel-air mixture on opposite sides of said restriction in the air intake line, said diaphragm being spring loaded.

3. A gas carbure-ting system comprising an air intake line, a fuel intake line connected to said air intake line, a selectiveiy controlled valve in said air intake line on the engine side of said fuel intake line for controlling the passage of a fuel-air mixture through said air intake line, a fuel supply regulatory valve connected to said fuel intake line, a fuel supply line connected to said fuel supply regulatory valve, said fuel supply regulatory valve having a restricted orifice through which fuel is supplied thereto, a flow control rod selectively positioned in said orifice, a pressure actuated diaphragm connected to and positioning said flow control rod, a restriction in said air intake line intermediate said fuel intake line and said first men- Itioned valve, one side of said diaphragm being communicated with said air intake line upstream of said restriction through said fuel intake line, a regulatory line communicating the other side of said diaphragm with said air intake line downstream of said restriction, whereby said diaphragm and said ow control rod are positioned by the difference in pressures on opposite sides of said restriction.

4. The gas carbureting system of claim 3 wherein said fuel intake line is very short as compared to said air intake line and of substantially the same cross-section as said air intake line.

5. The gas carbureting system of claim 3 wherein said fuel supply regulatory valve is mounted on and supported by said fuel intake line.

6. The gas carbureting system` of claim 3 wherein said fuel intake line is very short as compared to said air intake line and of substantially the same cross-section as said air intake line, said' fuel supply regulatory valve being n mounted on and supported by said fuel intake valve;

7. The gas carbureting system of claim 3 wherein said restricted orifice is in the form of a venturi.

8. The gas carbureting system of claim l wherein said shut-off valve includes a spring loaded diaphragm, a vacuum line having one end connected to said shut-off valve and an opposite end `adapted-tc be connected to an intake manifold whereby operati-on of an engine produces a sub-atmospheric pressure onl said spring loaded diaphragm to move said shut-off valve to an open position, said shut-off valve being normally urged to a closedposition by said spring loadeddiaphragm,

9. A gas carbureting system comprising an air intake line, a fuel intake line carried by and communicating with said air intake line, a fuel supply regulating valve in said fuel intake line, a fuel supply line connected to said fuel intake line, a fuel shut-olf valve disposed bet-weeny said vfuel supply line and said fuel intake line, a selectively control valve in said air intake line for controlling the passage of a fuel-air mixture therethrough, said fuel supply regulating valve including a restricted orifice, a flow control rod selectively positioned in said orifice, apressure actuated diaphragm, a restriction in said air intake line on the engine side of said fuel intake line, said diaphragm having one side communicated with the air intake line on the upstream side of the restriction in said air intake line, the other side of said diaphragm being communicated with the 'air intake line on the downstream side of said restriction in the air intake line, said References Cited in the le of this patent diaphragm being thus positioned by the difference in pres- UNITED STATES PATENTS sures of the fuei'air mixture.` on opposite sides of said restriction, said fuel control rod being connected .to said n ggg' one side of said diaphragm whereby the ow of fuel 5 2143194 Holzapvf Ian` 10 1939 through said orifice is increased in response to the lower- 2j155754 Ensign Apr: 25 1939 ing of the pressure on the downstream side of said restric- 2,209,206 Peduzzi July 23: 1940 tion' 2,689,172 Jones sept. 14, 1954 2,698,226 Peduzzi Dec. 28, 1954 

3. A GAS CARBURETING SYSTEM COMPRISING AN AIR INTAKE LINE, A FUEL INTAKE LINE CONNECTED TO SAID AIR INTAKE LINE, A GINE SIDE OF SAID FUEL INTAKE LINE FOR CONTROLLING THE PASSAGE OF A FUEL-AIR MIXTURE THROUGH SAID AIR INTAKE LINE, A FUEL SUPPLY REGULATORY VALVE CONNECTED TO SAID FUEL INTAKE LINE, A FUEL SUPPLY LINE CONNECTED TO SAID FUEL SUPPLY REGULATORY VALVE, SAID FUEL SUPPLY REGULATORY VALVE HAVING A RESTRICTED ORIFICE THROUGH WHICH FUEL IS SUPPLIED THERETO, A FLOW CONTROL ROD SELECTIVELY POSITIONED IN SAID ORIFICE, A PRESSURE ACTUATED DIAPHRAGM CONNECTED TO AND POSITIONING SAID FLOW CONTROL ROD, A RESTRICTION IN SAID AIR INTAKE LINE INTERMEDIATE SAID FUEL INTAKE LINE AND SAID FIRST MENTIONED VALVE, ONE SIDE OF SAID DIAPHRAGM BEING COMMUNICATED WITH SAID AIR INTAKE LINE UPSTREAM OF SAID RESTRICTION THROUGH SAID FUEL INTAKE LINE, A REGULATORY LINE COMMUNICATING THE OTHER SIDE OF SAID DIAPHRAGM WITH SAID AIR INTAKE LINE DOWNSTREAM OF SAID RESTRICTION, WHEREBY SAID DIAPHRAGM AND SAID FLOW CONTROL ROD ARE POSITIONED BY THE DIFFERENCE IN PRESSURES ON OPPOSITE SIDES OF SAID RESTRICTION. 